Telephone signaling appaeatus



(No Model.) 3 Sheets-Sheet 2.

W. J; DUDLEY.

TELEPHONE S IG-NALING A'PPARATUS. 7

No. 295,918. Patented Apr 1,1884

WITNE55E5 INIVIENTDR N. Fmns. PlwIo'Limagnphan'Wzshinglom u. c.

3 Sheets-Sheet 3.

(N0 Mddel.)

J. DUDLEY. TELEPHONE SIGNALING APPARATUS.

N0. 295.91s. Patented A r. 1, 1884.

- \A/ITNESEES $36M INVENTUR' k NIT-ED. ST TES PATENT Erica.

WALTER J. DUDLEY, OF EVERETT, MASSACHUSETTS, ASSIGNOR To THE -DUDLEY ELECTRIC MANUEAo UEINe COMPANY, or ooNooED, N. H.

TELEPHONE SIGNALING, APPARATUS.

$PECIFIC'A1ION forming part of Letters Patent No. 295,913, dated April 1, 1884.

Application filed June 19, 1883. (N model.)

To all whom it may concern Be it known that I, WALTER J. DUDLEY, of Everett, in the county of Micldlesex and State of Massachusetts, have invented certain Improvements in 'Telephone Signaling Apparatus, of which the following isaspecification.

This apparatus belongs to that class of elec- A trical signaling apparatus in which a series of electrical impulses operate-switching devices step by step, said devices co-operatlng with a lever actuated by a supplemental armature in amanner to be described. Devices for preserving unison are provided; also, devices peculiar to this apparatus for preventing any variation of line-resistance while step-by-step devices are operative; also, devices for allowing a bell to'be rung by ordinary alternating magneto-current when circuited by this apparatus without disturbance to said apparatus,

all of which I will now proceed to describe.

Of the accompanying drawings, forming a part of this specification, Figure 1 represents a front elevation of an apparatus embodying my improvements, and a diagram of the electrical connections. Fig. 2 represents a side elevation of the same. Fig. 3 represents a top plan view. Fig. irepresents an enlarged bottom plan view. Figs. 5, 6, 7, 8, 9, and 10 represent detail views showing different parts of the operation. i

The same letters of reference indicate the same parts in all the figures. In the drawings, 0 represents an electromagnet, supported by a frame composed, in

this instance, of two permanentmagnets, a a, and a bracket or cross-piece, 72, secured to the inner sides of said magnets, but magnetically insulated therefrom by copper washers c c, interposed between the bracket 1) and magnets a a. i

A B represent polarized armatures pivoted at 2' M0 the ends of the permanent magnets a a, and so polarized that their free ends are of like sign, so that they are simultaneously attracted or repelled by the electromagnet, each armature being composed of two arms, 2 2, connected bya cross-bar, 3. I prefer to make said arms and cross-bar3 in each armature of a single piece of iron, the cross-bar being much thinner than the arms 2 2, to diend with arms in m, having pallets m m,

adapted to alternately come in contact with the ratchet awhen the leverlis oscillated and rotate said ratchet and its arbor step by step. The lever Z'is oscillated by the intermittent currents sent through the electro-magnet and by the force of a retracting-spring, 0, which draws its free end away from the poles of the electro-magnet. I

To thearmature B is attached a lever, D, weighted by means of an adjustable weight, B, on an arm, 19, attached to said lever. The armature B is arranged to remain indifferently wherever left by thelast current-that is to say, either in contact with the poles of the electro-magnet or away from the same.

The lever D, actuated by the armature B, carries upon its free end the following devices, viz:

First. A cut-out spring, d, arranged, when the armature B is attracted, to make contact with a screw, d, whichis supported by but electrically insulated from the metal frame of the instrument, and is connected by wire 4' with the line out, as shown in Fig. 1. When such contact is made, all the telephonic apparatus at the station where the instrument is placed is short-circuited.

Secondly. A bell cut out consisting of a spring, e, normally in contact. with a metal contact-point, 0, supported by but insulated from the lever D, and connected by wire 5 with the magnetogenerator 6 of the station and with line out, thereby short-circuiting the magneto-bell 7 Thirdly. A projection, f, arranged to be moved into or out of the path of a similar proj ection, f, on ratchet-wheel a, to preserve unison.

Fourthly. A spring-catch, g, co-operating with a pin, It,- in a disk, it, on the arbor j, to limit the play of the-armature B, and thereby prevent it from being brought into permanent contact with the electro-magnet whenever the bell 7 governed by the apparatus, is operative. V

Fifthly. A spring, L, co-operating with the disk It and with the spring 0, to render the armature B sensitive to slight attractive currents.

The ratchet-wheel a is provided with a pin, 1'', which is adapted once during each rotation of the arborj to form a stop for the springc,

\ and separate the latter from its conta ct 0 when the armature B is repelled and its lever D is thrown inwardly, as hereinafter described.

Operation: It will be convenient to call a current of the proper direction or polarity to attract the armatures an attractive current and its opposite a repellent current. In the normal state-of the apparatus, with the line unoccupied and the indicator-hand on zero, both armatures will be away from the electromagnet, and a repellent current would, if sent to line, take the following path in any one apparatus: to binding-post 8, through the coils of the electro-magnet to the frame of the instrument, spring 0, its contact 6, wire 8 5 5, post 9, through the office telephone apparatus,eXcept the bell,and on to the next office. Thus it is evident the hell 7 is out of circuit. Now, if a subscriber at the station in question call the exchange by a crank-magneto,

the armature A will be unaffectethas its spring is too strong to be overcome by such weak currents; but armature B,being lightly poised, is affected, and means must be provided to prevent it from making a permanentcontact with its electromagnet O,or else the calling station would cut itself out on the first turn of its magneto. To this end the projection f on the armature-lever D and the co-operating projection f on the ratchet-wheel a are em ployed, the latter being located outside of the former when the pointer is is at zero, so

that the armature 13 cannot make contact withthe electromagnet, its play being limited by the projection f, as shown in Fig. 5. If an attractive current be sent to line, and in the office under considerationsubscriber has his telephone T circuited, the extra resistance might make the current too weak to operate armature A; but it would operate armature B, which, in the condition last described, has sufficient play to allow spring (I to make yielding contact with screw (1. The current im .mediately has a new path, as follows: to post her. At this point a repellent current is sent, causing armature B toseparatefrom the electro-magnet, and of course breaking the connection between d cl, and as at this time the pin 1' in wheel a is under the end of spring 0, the movement of armature-lever D causes said pin to engage said spring and break its contact'with e, as shown in Fig. 6, thereby circuiting the bell, which is then rung by a magnetocurrent. The restoration to the zero-point at the conclusion of a message is effected by a number of attractive followed by a repellent impulse, the armature B being held to the poles of the magnet by the attractive impulses, and thus holding its projection f in the path of the projectionf until the former arrests the latter, as shown in Fig. 7, the pointer being then nearly at zero, and the armature of lever l attracted to the electro-magnet, the pallets m on being in position to give the ratchet-wheel a forward step. The repellent impulse is then given, causing the armatures A B and their levers to assume the positions shown in Fig. 5, the projection f releasing the projection f, so that the armature A, in moving away from the electro-magnet' under the influence of the retraetile spring, gives the ratchet a step forward, and thus brings the pointer to unison.

It is quite important to prevent the armature B from sticking to the electro-magnet (throughthe magneto-currents) at the called office. To this end the catch 9, cooperating with pin h in disk It at the office-number, is provided. Said catch engages the pin h, as shown in Fig. 3, when the office-number is reached. By said pin the play of the armature B is limited as at the zero-point, and as the mass of the armature l3 and its attachments is quite large, and its movements quite slow in comparison with those of the armature of a magneto-bell, the momentary contacts between d and cl do not affect the bell.

The weight B must be located far enough away from lever D to overcome the tension of the spring 6 when the latteris engaged by the pin 1' on the wheel a; but when said spring is disengaged the weight B is excessive and prevents the armature B from responding to weakcurrents, I therefore provide the spring 1', which, by striking the periphery of the disk h, becomes the equivalent of spring 6, being prevented from acting simultaneously with the sameby a notch, if, in said disk, in which an offset, 1', on said spring plays, as shown in Fig. 9, when spring 6 is engaged by the pin 1' in wheel a. The armature B isthus enabled to respond to comparatively weak as well as to stronger currents.

It will be borne in mind that the pin h on the disk It will be differently located in each instrument in the circuit, so that it will engage the catch g at only one station at a time.

The projection f is beveled on the side which is adjacent to the pin f when the parts are in the position shown in Fig. 5, so that when the lever D is moved outwardly by the next attractive impulse through the electromagnet the beveled side of theprojection f, striking the pinf, will not impede the rotation of the ratchet-wheel, but will have a wedge or cam i like action on said pin, facilitating the rotation vof the ratchet.

12 represents a spring which bears with a yielding pressure against one end of the arbor j and acts as a brake to prevent the arbor from being rotated more than one step at a time,this action being due not only to the direct bearing of the spring on the end of the arbor, but also to the endwise pressure imparted to the arbor by the spring, which presses a shoulder, 12, on the arbor against a bearing, w, which may, if desired, be a yielding spring-plate interposed between said shoulder and a fixed surface. (See Fig. 10.) The spring may be adjusted to vary its pressure on the arbor by means of a screw,

tracted and repelled, the armature A being provided with a retractile spring and the other being poised lightly, an arbor adapted to be rotated step by step by the lever of armature A, and switching devices, substantially as described, operated by the lever of armature B, whereby, when theinstrnments are at unison and repellent currents are sent to line, the bell of the station or office where the instrument is located is thrown out of circuit, as set forth.

2. The combination of an electro-magnet,

'the polarized armatures A B and their operating-levers, the arbor adapted to be rotated step by step, as described, means whereby the armature Bis prevented from making con tact with the electro-magnet when the central office is being called, and switching devices operated by the lever of armature B,

wherebythe entire telephonic resistance at.

the calling station is cut out and the full strength of the current is applied to rotating the arbor to the office-number, as set forth.

3. The combination of anelectro-niagnet, the polarized armatures A B and their operating-levers, an insulated contact-point anda 1 spring therefor on the lever of armature B,

normally short-eircuiting the bell at the station where the apparatus is located, the arbor adapted to be rotated step by step, as described, and provided with a stop or pin adapted to separate said spring from its contact-point, and thereby circuit the bell and permit the latter to be rung by a magnetocurrent, as set forth.

4. The combination of an electro-magnet, the polarized armatures A B and their operatingleversl and D, the latter having a projection, f, the arbor adapted to be rotated step by step, and provided with a pin, f,

adapted to cooperate with the projection f and arrest tliearb'or near the zero-point, as set forth. 5. The combination of an electro-magnet,

the polarized armatnres A B and their operating-levers, the arbor adapted to be rotated step by step, and means whereby the movement of the armature B and its lever is an rested when the arbor is rotated to the officenumber, as set forth.

6. The combination of the arbor rotated step by step, as'described, and provided with the pin 1* and notched disk h, and the weighted armature-lever D, provided with the springs e and 2', adapted to act, respectively, on the pin 1' and the periphery of the disk h, whereby the influence of the weight of the armature-lever is partiallycounteracted and the armature is enabled to respond to weak currents, as set forth.

7. The combination, withthe step-by-steprotated arbor j, having a shoulder, o, of the spring 1), bearing against the end of said arbor, and pressing the shoulder thereof against a bearingsurface, as set forth.

8. The combination, with the arbor j and its adjusting-spring v, of means for varying the pressure of said spring, as set forth.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 6th day of June, 1883.

. WALTE J. DUDLEY.

Witnesses;

O. F. BROWN, A. L. WHITE. 

